Added real unit tests for resource

CONTRIBUTING.md

@@ -8,10 +8,11 @@ Contributing to Databricks Terraform Provider
 - [Building and Installing with Docker](#building-and-installing-with-docker)
 - [Testing](#testing)
 - [Linting](#linting)
+- [Unit testing resources](#unit-testing-resources)
 - [Integration Testing](#integration-testing)
 - [Project Components](#project-components)
-  - [Databricks Terraform Provider Resources State](#databricks-terraform-provider-resources-state)
-  - [Databricks Terraform Data Sources State](#databricks-terraform-data-sources-state)
+	- [Databricks Terraform Provider Resources State](#databricks-terraform-provider-resources-state)
+	- [Databricks Terraform Data Sources State](#databricks-terraform-data-sources-state)
 
 We happily welcome contributions to databricks-terraform. We use GitHub Issues to track community reported issues and GitHub Pull Requests for accepting changes.
 
@@ -128,6 +129,67 @@ $ docker run -it -v $(pwd):/workpace -w /workpace databricks-terraform apply
 Please use makefile for linting. If you run `golangci-lint` by itself it will fail due to different tags containing same functions. 
 So please run `make lint` instead.
 
+## Unit testing resources
+
+In order to unit test a resource, which runs fast and could be included in code coverage, one should use `ResourceTester`, that launches embedded HTTP server with `HTTPFixture`'s containing all calls that should have been made in given scenario. Some may argue that this is not a pure unit test, because it creates a side effect in form of embedded server, though it's always on different random port, making it possible to execute these tests in parallel. Therefore comments about non-pure unit tests will be ignored, if they use `ResourceTester` helper.
+
+```go
+func TestPermissionsCreate(t *testing.T) {
+	_, err := ResourceTester(t, []HTTPFixture{
+		{
+            Method:   http.MethodPatch,
+            // requires full URI
+            Resource: "/api/2.0/preview/permissions/clusters/abc",
+            // works with entities, not JSON. Diff is displayed in case of missmatch 
+			ExpectedRequest: model.AccessControlChangeList{
+				AccessControlList: []*model.AccessControlChange{
+					{
+						UserName:        &TestingUser,
+						PermissionLevel: "CAN_USE",
+					},
+				},
+			},
+		},
+		{
+			Method:   http.MethodGet,
+			Resource: "/api/2.0/preview/permissions/clusters/abc?",
+			Response: model.AccessControlChangeList{
+				AccessControlList: []*model.AccessControlChange{
+					{
+						UserName:        &TestingUser,
+						PermissionLevel: "CAN_MANAGE",
+					},
+				},
+			},
+		},
+		{
+			Method:   http.MethodGet,
+			Resource: "/api/2.0/preview/scim/v2/Me?",
+			Response: model.User{
+				UserName: "chuck.norris",
+			},
+		},
+    }, 
+    // next argument is function, that creates resource (to make schema for ResourceData)
+    resourcePermissions, 
+    // state represented as native structure (though a bit clunky)
+    map[string]interface{}{
+		"cluster_id": "abc",
+		"access_control": []interface{}{
+			map[string]interface{}{
+				"user_name":        TestingUser,
+				"permission_level": "CAN_USE",
+			},
+		},
+    },
+    // the last argument is a function, that performs a stage on resource (Create/update/delete/read)
+    resourcePermissionsCreate)
+	assert.NoError(t, err, err)
+}
+```
+
+Each resource should have both unit and integration tests. 
+
 ## Integration Testing
 
 Currently Databricks supports two cloud providers `azure` and `aws` thus integration testing with the correct cloud service provider is 
@@ -162,7 +224,6 @@ DATABRICKS_AZURE_WORKSPACE_NAME=<azure databricks workspace name>
 Note that azure integration tests will use service principal based auth. Even though it is using a service principal, 
 it will still be generating a personal access token to perform creation of resources. 
 
-
 ## Project Components
 
 ### Databricks Terraform Provider Resources State

databricks/resource_databricks_permissions.go

@@ -33,6 +33,7 @@ func parsePermissionsFromData(d *schema.ResourceData,
 	if objectID == "" {
 		return nil, "", fmt.Errorf("At least one type of resource identifiers must be set")
 	}
+	changes := 0
 	if data, ok := d.GetOk("access_control"); ok {
 		for _, element := range data.([]interface{}) {
 			rawAccessControl := element.(map[string]interface{})
@@ -47,8 +48,12 @@ func parsePermissionsFromData(d *schema.ResourceData,
 			if v, ok := rawAccessControl["permission_level"].(string); ok {
 				change.PermissionLevel = v
 			}
+			changes++
 		}
 	}
+	if changes < 1 {
+		return nil, "", fmt.Errorf("At least one access_control is required")
+	}
 	return acl, objectID, nil
 }
 

databricks/resource_databricks_permissions_test.go

@@ -2,16 +2,166 @@ package databricks
 
 import (
 	"fmt"
+	"net/http"
 	"testing"
 
 	"github.com/hashicorp/terraform-plugin-sdk/helper/acctest"
 	"github.com/hashicorp/terraform-plugin-sdk/helper/resource"
+	"github.com/hashicorp/terraform-plugin-sdk/helper/schema"
 	"github.com/stretchr/testify/assert"
 
 	"github.com/databrickslabs/databricks-terraform/client/model"
 	"github.com/databrickslabs/databricks-terraform/client/service"
 )
 
+var (
+	TestingUser      = "ben"
+	TestingAdminUser = "admin"
+)
+
+func TestPermissionsRead(t *testing.T) {
+	d, err := ResourceTester(t, []HTTPFixture{
+		{
+			Method:   http.MethodGet,
+			Resource: "/api/2.0/preview/permissions/clusters/abc?",
+			Response: model.ObjectACL{
+				ObjectID:   "/clusters/abc",
+				ObjectType: "clusters",
+				AccessControlList: []*model.AccessControl{
+					{
+						UserName: &TestingUser,
+						AllPermissions: []*model.Permission{
+							{
+								PermissionLevel: "CAN_READ",
+								Inherited:       false,
+							},
+						},
+					},
+					{
+						UserName: &TestingAdminUser,
+						AllPermissions: []*model.Permission{
+							{
+								PermissionLevel: "CAN_MANAGE",
+								Inherited:       false,
+							},
+						},
+					},
+				},
+			},
+		},
+		{
+			Method:   http.MethodGet,
+			Resource: "/api/2.0/preview/scim/v2/Me?",
+			Response: model.User{
+				UserName: TestingAdminUser,
+			},
+		},
+	}, resourcePermissions, map[string]interface{}{},
+		func(d *schema.ResourceData, c interface{}) error {
+			d.SetId("/clusters/abc")
+			return resourcePermissionsRead(d, c)
+		})
+	assert.NoError(t, err, err)
+	assert.Equal(t, "/clusters/abc", d.Id())
+	assert.Equal(t, TestingUser, d.Get("access_control.0.user_name"))
+	assert.Equal(t, "CAN_READ", d.Get("access_control.0.permission_level"))
+	assert.Equal(t, 1, d.Get("access_control.#"))
+}
+
+func TestPermissionsDelete(t *testing.T) {
+	d, err := ResourceTester(t, []HTTPFixture{
+		{
+			Method:          http.MethodPut,
+			Resource:        "/api/2.0/preview/permissions/clusters/abc",
+			ExpectedRequest: model.ObjectACL{},
+		},
+	}, resourcePermissions, map[string]interface{}{},
+		func(d *schema.ResourceData, c interface{}) error {
+			d.SetId("/clusters/abc")
+			return resourcePermissionsDelete(d, c)
+		})
+	assert.NoError(t, err, err)
+	assert.Equal(t, "/clusters/abc", d.Id())
+}
+
+func TestPermissionsCreate_invalid(t *testing.T) {
+	_, err := ResourceTester(t, []HTTPFixture{}, resourcePermissions, map[string]interface{}{},
+		resourcePermissionsCreate)
+	assert.EqualError(t, err, "At least one type of resource identifiers must be set")
+}
+
+func TestPermissionsCreate_no_access_control(t *testing.T) {
+	_, err := ResourceTester(t, []HTTPFixture{}, resourcePermissions,
+		map[string]interface{}{
+			"cluster_id": "abc",
+		}, resourcePermissionsCreate)
+	assert.EqualError(t, err, "At least one access_control is required")
+}
+
+func TestPermissionsCreate(t *testing.T) {
+	d, err := ResourceTester(t, []HTTPFixture{
+		{
+			Method:   http.MethodPatch,
+			Resource: "/api/2.0/preview/permissions/clusters/abc",
+			ExpectedRequest: model.AccessControlChangeList{
+				AccessControlList: []*model.AccessControlChange{
+					{
+						UserName:        &TestingUser,
+						PermissionLevel: "CAN_USE",
+					},
+				},
+			},
+		},
+		{
+			Method:   http.MethodGet,
+			Resource: "/api/2.0/preview/permissions/clusters/abc?",
+			Response: model.ObjectACL{
+				ObjectID:   "/clusters/abc",
+				ObjectType: "clusters",
+				AccessControlList: []*model.AccessControl{
+					{
+						UserName: &TestingUser,
+						AllPermissions: []*model.Permission{
+							{
+								PermissionLevel: "CAN_READ",
+								Inherited:       false,
+							},
+						},
+					},
+					{
+						UserName: &TestingAdminUser,
+						AllPermissions: []*model.Permission{
+							{
+								PermissionLevel: "CAN_MANAGE",
+								Inherited:       false,
+							},
+						},
+					},
+				},
+			},
+		},
+		{
+			Method:   http.MethodGet,
+			Resource: "/api/2.0/preview/scim/v2/Me?",
+			Response: model.User{
+				UserName: TestingAdminUser,
+			},
+		},
+	}, resourcePermissions, map[string]interface{}{
+		"cluster_id": "abc",
+		"access_control": []interface{}{
+			map[string]interface{}{
+				"user_name":        TestingUser,
+				"permission_level": "CAN_USE",
+			},
+		},
+	}, resourcePermissionsCreate)
+	assert.NoError(t, err, err)
+	assert.Equal(t, TestingUser, d.Get("access_control.0.user_name"))
+	assert.Equal(t, "CAN_READ", d.Get("access_control.0.permission_level"))
+	assert.Equal(t, 1, d.Get("access_control.#"))
+}
+
 func TestAccDatabricksPermissionsResourceFullLifecycle(t *testing.T) {
 	var permissions model.ObjectACL
 	randomName := acctest.RandStringFromCharSet(10, acctest.CharSetAlphaNum)

databricks/utils_test.go

@@ -260,6 +260,80 @@ func testVerifyResourceIsMissing(t *testing.T, readFunc func() error) {
 			"\nerror code: %s",
 			apiError, apiError.StatusCode, apiError.ErrorCode))
 	}
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/databrickslabs/databricks-terraform/client/service"
+	"github.com/hashicorp/terraform-plugin-sdk/helper/schema"
+	"github.com/stretchr/testify/assert"
+)
+
+// HTTPFixture defines request structure for test
+type HTTPFixture struct {
+	Method          string
+	Resource        string
+	Response        interface{}
+	Status          int
+	ExpectedRequest interface{}
+}
+
+// ResourceTester helps testing HTTP resources with fixtures
+func ResourceTester(t *testing.T,
+	fixtures []HTTPFixture,
+	resouceFunc func() *schema.Resource,
+	state map[string]interface{},
+	whatever func(d *schema.ResourceData, c interface{}) error) (*schema.ResourceData, error) {
+	server := httptest.NewServer(http.HandlerFunc(func(rw http.ResponseWriter, req *http.Request) {
+		found := false
+		for _, fixture := range fixtures {
+			if req.Method == fixture.Method && req.RequestURI == fixture.Resource {
+				if fixture.Status == 0 {
+					rw.WriteHeader(200)
+				} else {
+					rw.WriteHeader(fixture.Status)
+				}
+				if fixture.ExpectedRequest != nil {
+					buf := new(bytes.Buffer)
+					_, err := buf.ReadFrom(req.Body)
+					assert.NoError(t, err, err)
+					jsonStr, err := json.Marshal(fixture.ExpectedRequest)
+					assert.NoError(t, err, err)
+					assert.JSONEq(t, string(jsonStr), buf.String())
+				}
+				if fixture.Response != nil {
+					responseBytes, err := json.Marshal(fixture.Response)
+					if err != nil {
+						assert.NoError(t, err, err)
+						t.FailNow()
+					}
+					_, err = rw.Write(responseBytes)
+					assert.NoError(t, err, err)
+				}
+				found = true
+				break
+			}
+		}
+		if !found {
+			assert.Fail(t, fmt.Sprintf("Received unexpected call: %s %s", req.Method, req.RequestURI))
+			t.FailNow()
+		}
+	}))
+
+	defer server.Close()
+	var config service.DBApiClientConfig
+	config.Host = server.URL
+	config.Setup()
+
+	var client service.DBApiClient
+	client.SetConfig(&config)
+
+	resource := resouceFunc()
+	resourceData := schema.TestResourceDataRaw(t, resource.Schema, state)
+	return resourceData, whatever(resourceData, &client)
 }
 
 func TestIsClusterMissingTrueWhenClusterIdSpecifiedPresent(t *testing.T) {

go.sum

@@ -147,6 +147,7 @@ github.com/hashicorp/terraform-svchost v0.0.0-20191011084731-65d371908596/go.mod
 github.com/hashicorp/yamux v0.0.0-20180604194846-3520598351bb/go.mod h1:+NfK9FKeTrX5uv1uIXGdwYDTeHna2qgaIlx54MXqjAM=
 github.com/hashicorp/yamux v0.0.0-20181012175058-2f1d1f20f75d h1:kJCB4vdITiW1eC1vq2e6IsrXKrZit1bv/TDYFGMp4BQ=
 github.com/hashicorp/yamux v0.0.0-20181012175058-2f1d1f20f75d/go.mod h1:+NfK9FKeTrX5uv1uIXGdwYDTeHna2qgaIlx54MXqjAM=
+github.com/jhump/protoreflect v1.6.0 h1:h5jfMVslIg6l29nsMs0D8Wj17RDVdNYti0vDN/PZZoE=
 github.com/jhump/protoreflect v1.6.0/go.mod h1:eaTn3RZAmMBcV0fifFvlm6VHNz3wSkYyXYWUh7ymB74=
 github.com/jmespath/go-jmespath v0.0.0-20160202185014-0b12d6b521d8/go.mod h1:Nht3zPeWKUH0NzdCt2Blrr5ys8VGpn0CEB0cQHVjt7k=
 github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af h1:pmfjZENx5imkbgOkpRUYLnmbU7UEFbjtDA2hxJ1ichM=